In the field of fiber lasers and amplifiers, recent developments have been focused on improving power, efficiency, beam quality and packaging characteristics. One of the difficult tasks in this field of fiber lasers is power scalability, since output power for individual fiber lasers and amplifiers is still limited to less than 10 kW due to the small lasing core area and heat-sink limitations. Nevertheless, there are a variety of applications that need a high-power laser source, and the primary approach to achieving this is to employ a beam combining (BC) technique to produce a multi-fiber laser source that can be scalable to high power. Such techniques still suffer from one or more of the following: lack of high efficiency, degraded beam quality, constraints on individual laser characteristics, system complexity, packaging constraints and need for free-space optics or an optical bench. These beam combining techniques still suffer from not being scalable to powers of 100 kW or more.